import sys

X = int(input())

if X >= 30:
    print('Yes')
else:
    print('No')

print('Yes\nNo', file=sys.stderr) import sys sys X = int(input()) X int(input()) int input() input if X >= 30:
    print('Yes')
else:
    print('No') X >= 30 X 30 print('Yes') print 'Yes' print('No') print 'No' print('Yes\nNo', file=sys.stderr) print 'Yes\nNo' file=sys.stderr file sys.stderr sys stderr X = int(input()) int(input()) X
import sys

X = int(input())

if X >= 30:
    print('Yes')
else:
    print('No')

print('Yes\nNo', file=sys.stderr)
